The hallmarks of an unstable student can show up in notebook doodles, essay responses, hallway chatter and snide jokes. And these days, county teachers and administrators say, no hint of violence can be treated as jest or a prank.

In the wake of deadly shootings on campuses from Arkansas to Oregon, Ventura County school officials say they are taking student threats of violence very seriously.

To assist concerned teachers, the National School Safety Center on Wednesday released its "assessment tool for predicting violent juvenile behavior," based on a study of the 230 school-related violent deaths that have occurred nationwide since 1992.

The 20-point checklist includes everything from children who have macabre taste in reading materials, music and essay topics to those who torture animals or obsess about bombs and weapons.

The concern about student safety hit close to home just this week when Adolfo Camarillo High School parents received a letter notifying them that a ninth-grader was in custody after threatening to shoot himself and others.

The unidentified young man faces arraignment and a detention hearing today on three felony counts of weapons possession for an implement other than a gun or bomb and two felony counts of making credible threats, said Miles Weiss, supervisor of the juvenile prosecution unit of the county district attorney's office.

The student could face almost six years of detention in the California Youth Authority.

Threats of violence on campus are rare, but student shooting sprees elsewhere have amplified sensitivity to violence, said Camarillo Principal Terry Tackett.

"If it has to do with safety, we take everything seriously," Tackett said. "We don't take anything as a joke."

Paying attention to students' mental well-being, just like checking their homework, has long been part of the job for teachers. But as youngsters have access to more firepower, the pressures on educators escalate, said Ronald D. Stephens, executive director of the National School Safety Center in Westlake Village.

"The demands are much greater on teachers today than ever before," Stephens said. "We do expect them not just to have academic smarts but to also have [street] savvy about the children with whom they deal."

While many items on the newly-released list are common-sensical, educators countywide said they would welcome the extra guidance.

Educators "are in a quasi-parental role, where we care about everything kids do," said county Supt. Charles Weis. "Parents want us in that role; they expect us to listen, pay attention, intervene when kids need help and give good advice."

That means that a student who jokes about a gun will be treated with the same care as a student caught bearing one.

"One child in severe pain who decides to act it out on others can shatter lives," Weis said. "We'd rather react--even overreact--to that child than have victims."

If a kid makes a tasteless joke about shooting the teacher who gave him an F, a referral to the principal or counselor is in order, educators say. If the comment was a joke, the student can acknowledge it and learn about the limits of appropriate classroom conduct. If the student meant it, he could get help. He could also face punishment up to expulsion and a referral to the police.

"We're not talking about the class clown here," said Hal Vick, executive director of teachers unions in Simi Valley and Conejo Valley area. "There are some students who are troubled, and teachers know who they are."

By all accounts, such referrals are uncommon.

Jean Wise, a counselor at Buena High School in Ventura, said the fact that school officials are looking out for hints that students may be troubled is nothing new. In past years, the vigilance has tagged things like depression or frustration among students, Wise said.

"We haven't seen any violent threats, but it's good to know we'd do something about it if we did," Wise said. "The worst I've seen is a student saying they hate their family or teacher, which is not extremely uncommon. We talk about it and find out where the student is coming from."

Santa Paula High School counselor Roger Ferris said English teachers already occasionally report students who have written disturbing passages in essays.

"We'll counsel the student on the spot," Ferris said. "And if a real threat or weapon is involved, it doesn't stop at this office. It will go all the way to the superintendent and possible expulsion. We don't fool around."

Ferris said he feels it is important to not ignore improper jokes made by even the most seemingly well-balanced student.

"We can't say, 'Oh, he's too nice a kid to do anything,' " he said. "Too much lately, schools haven't taken threats seriously, and look what's happened. We need to be more on the ball and follow up on all threats immediately."

Mere talk or jokes about using guns or bombs at school is enough to warrant action against the student, Ferris said.

"We don't think any threat is funny," he said. "If they're willing to talk about it, that means they've thought about it and there could be a motive."